diff options
Diffstat (limited to 'drivers/thunderbolt/ctl.c')
| -rw-r--r-- | drivers/thunderbolt/ctl.c | 1144 |
1 files changed, 1144 insertions, 0 deletions
diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c new file mode 100644 index 0000000000..d997a4c545 --- /dev/null +++ b/drivers/thunderbolt/ctl.c @@ -0,0 +1,1144 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt driver - control channel and configuration commands + * + * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> + * Copyright (C) 2018, Intel Corporation + */ + +#include <linux/crc32.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/pci.h> +#include <linux/dmapool.h> +#include <linux/workqueue.h> + +#include "ctl.h" + + +#define TB_CTL_RX_PKG_COUNT 10 +#define TB_CTL_RETRIES 4 + +/** + * struct tb_ctl - Thunderbolt control channel + * @nhi: Pointer to the NHI structure + * @tx: Transmit ring + * @rx: Receive ring + * @frame_pool: DMA pool for control messages + * @rx_packets: Received control messages + * @request_queue_lock: Lock protecting @request_queue + * @request_queue: List of outstanding requests + * @running: Is the control channel running at the moment + * @timeout_msec: Default timeout for non-raw control messages + * @callback: Callback called when hotplug message is received + * @callback_data: Data passed to @callback + */ +struct tb_ctl { + struct tb_nhi *nhi; + struct tb_ring *tx; + struct tb_ring *rx; + + struct dma_pool *frame_pool; + struct ctl_pkg *rx_packets[TB_CTL_RX_PKG_COUNT]; + struct mutex request_queue_lock; + struct list_head request_queue; + bool running; + + int timeout_msec; + event_cb callback; + void *callback_data; +}; + + +#define tb_ctl_WARN(ctl, format, arg...) \ + dev_WARN(&(ctl)->nhi->pdev->dev, format, ## arg) + +#define tb_ctl_err(ctl, format, arg...) \ + dev_err(&(ctl)->nhi->pdev->dev, format, ## arg) + +#define tb_ctl_warn(ctl, format, arg...) \ + dev_warn(&(ctl)->nhi->pdev->dev, format, ## arg) + +#define tb_ctl_info(ctl, format, arg...) \ + dev_info(&(ctl)->nhi->pdev->dev, format, ## arg) + +#define tb_ctl_dbg(ctl, format, arg...) \ + dev_dbg(&(ctl)->nhi->pdev->dev, format, ## arg) + +static DECLARE_WAIT_QUEUE_HEAD(tb_cfg_request_cancel_queue); +/* Serializes access to request kref_get/put */ +static DEFINE_MUTEX(tb_cfg_request_lock); + +/** + * tb_cfg_request_alloc() - Allocates a new config request + * + * This is refcounted object so when you are done with this, call + * tb_cfg_request_put() to it. + */ +struct tb_cfg_request *tb_cfg_request_alloc(void) +{ + struct tb_cfg_request *req; + + req = kzalloc(sizeof(*req), GFP_KERNEL); + if (!req) + return NULL; + + kref_init(&req->kref); + + return req; +} + +/** + * tb_cfg_request_get() - Increase refcount of a request + * @req: Request whose refcount is increased + */ +void tb_cfg_request_get(struct tb_cfg_request *req) +{ + mutex_lock(&tb_cfg_request_lock); + kref_get(&req->kref); + mutex_unlock(&tb_cfg_request_lock); +} + +static void tb_cfg_request_destroy(struct kref *kref) +{ + struct tb_cfg_request *req = container_of(kref, typeof(*req), kref); + + kfree(req); +} + +/** + * tb_cfg_request_put() - Decrease refcount and possibly release the request + * @req: Request whose refcount is decreased + * + * Call this function when you are done with the request. When refcount + * goes to %0 the object is released. + */ +void tb_cfg_request_put(struct tb_cfg_request *req) +{ + mutex_lock(&tb_cfg_request_lock); + kref_put(&req->kref, tb_cfg_request_destroy); + mutex_unlock(&tb_cfg_request_lock); +} + +static int tb_cfg_request_enqueue(struct tb_ctl *ctl, + struct tb_cfg_request *req) +{ + WARN_ON(test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags)); + WARN_ON(req->ctl); + + mutex_lock(&ctl->request_queue_lock); + if (!ctl->running) { + mutex_unlock(&ctl->request_queue_lock); + return -ENOTCONN; + } + req->ctl = ctl; + list_add_tail(&req->list, &ctl->request_queue); + set_bit(TB_CFG_REQUEST_ACTIVE, &req->flags); + mutex_unlock(&ctl->request_queue_lock); + return 0; +} + +static void tb_cfg_request_dequeue(struct tb_cfg_request *req) +{ + struct tb_ctl *ctl = req->ctl; + + mutex_lock(&ctl->request_queue_lock); + list_del(&req->list); + clear_bit(TB_CFG_REQUEST_ACTIVE, &req->flags); + if (test_bit(TB_CFG_REQUEST_CANCELED, &req->flags)) + wake_up(&tb_cfg_request_cancel_queue); + mutex_unlock(&ctl->request_queue_lock); +} + +static bool tb_cfg_request_is_active(struct tb_cfg_request *req) +{ + return test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags); +} + +static struct tb_cfg_request * +tb_cfg_request_find(struct tb_ctl *ctl, struct ctl_pkg *pkg) +{ + struct tb_cfg_request *req = NULL, *iter; + + mutex_lock(&pkg->ctl->request_queue_lock); + list_for_each_entry(iter, &pkg->ctl->request_queue, list) { + tb_cfg_request_get(iter); + if (iter->match(iter, pkg)) { + req = iter; + break; + } + tb_cfg_request_put(iter); + } + mutex_unlock(&pkg->ctl->request_queue_lock); + + return req; +} + +/* utility functions */ + + +static int check_header(const struct ctl_pkg *pkg, u32 len, + enum tb_cfg_pkg_type type, u64 route) +{ + struct tb_cfg_header *header = pkg->buffer; + + /* check frame, TODO: frame flags */ + if (WARN(len != pkg->frame.size, + "wrong framesize (expected %#x, got %#x)\n", + len, pkg->frame.size)) + return -EIO; + if (WARN(type != pkg->frame.eof, "wrong eof (expected %#x, got %#x)\n", + type, pkg->frame.eof)) + return -EIO; + if (WARN(pkg->frame.sof, "wrong sof (expected 0x0, got %#x)\n", + pkg->frame.sof)) + return -EIO; + + /* check header */ + if (WARN(header->unknown != 1 << 9, + "header->unknown is %#x\n", header->unknown)) + return -EIO; + if (WARN(route != tb_cfg_get_route(header), + "wrong route (expected %llx, got %llx)", + route, tb_cfg_get_route(header))) + return -EIO; + return 0; +} + +static int check_config_address(struct tb_cfg_address addr, + enum tb_cfg_space space, u32 offset, + u32 length) +{ + if (WARN(addr.zero, "addr.zero is %#x\n", addr.zero)) + return -EIO; + if (WARN(space != addr.space, "wrong space (expected %x, got %x\n)", + space, addr.space)) + return -EIO; + if (WARN(offset != addr.offset, "wrong offset (expected %x, got %x\n)", + offset, addr.offset)) + return -EIO; + if (WARN(length != addr.length, "wrong space (expected %x, got %x\n)", + length, addr.length)) + return -EIO; + /* + * We cannot check addr->port as it is set to the upstream port of the + * sender. + */ + return 0; +} + +static struct tb_cfg_result decode_error(const struct ctl_pkg *response) +{ + struct cfg_error_pkg *pkg = response->buffer; + struct tb_cfg_result res = { 0 }; + res.response_route = tb_cfg_get_route(&pkg->header); + res.response_port = 0; + res.err = check_header(response, sizeof(*pkg), TB_CFG_PKG_ERROR, + tb_cfg_get_route(&pkg->header)); + if (res.err) + return res; + + res.err = 1; + res.tb_error = pkg->error; + res.response_port = pkg->port; + return res; + +} + +static struct tb_cfg_result parse_header(const struct ctl_pkg *pkg, u32 len, + enum tb_cfg_pkg_type type, u64 route) +{ + struct tb_cfg_header *header = pkg->buffer; + struct tb_cfg_result res = { 0 }; + + if (pkg->frame.eof == TB_CFG_PKG_ERROR) + return decode_error(pkg); + + res.response_port = 0; /* will be updated later for cfg_read/write */ + res.response_route = tb_cfg_get_route(header); + res.err = check_header(pkg, len, type, route); + return res; +} + +static void tb_cfg_print_error(struct tb_ctl *ctl, + const struct tb_cfg_result *res) +{ + WARN_ON(res->err != 1); + switch (res->tb_error) { + case TB_CFG_ERROR_PORT_NOT_CONNECTED: + /* Port is not connected. This can happen during surprise + * removal. Do not warn. */ + return; + case TB_CFG_ERROR_INVALID_CONFIG_SPACE: + /* + * Invalid cfg_space/offset/length combination in + * cfg_read/cfg_write. + */ + tb_ctl_dbg(ctl, "%llx:%x: invalid config space or offset\n", + res->response_route, res->response_port); + return; + case TB_CFG_ERROR_NO_SUCH_PORT: + /* + * - The route contains a non-existent port. + * - The route contains a non-PHY port (e.g. PCIe). + * - The port in cfg_read/cfg_write does not exist. + */ + tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Invalid port\n", + res->response_route, res->response_port); + return; + case TB_CFG_ERROR_LOOP: + tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Route contains a loop\n", + res->response_route, res->response_port); + return; + case TB_CFG_ERROR_LOCK: + tb_ctl_warn(ctl, "%llx:%x: downstream port is locked\n", + res->response_route, res->response_port); + return; + default: + /* 5,6,7,9 and 11 are also valid error codes */ + tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Unknown error\n", + res->response_route, res->response_port); + return; + } +} + +static __be32 tb_crc(const void *data, size_t len) +{ + return cpu_to_be32(~__crc32c_le(~0, data, len)); +} + +static void tb_ctl_pkg_free(struct ctl_pkg *pkg) +{ + if (pkg) { + dma_pool_free(pkg->ctl->frame_pool, + pkg->buffer, pkg->frame.buffer_phy); + kfree(pkg); + } +} + +static struct ctl_pkg *tb_ctl_pkg_alloc(struct tb_ctl *ctl) +{ + struct ctl_pkg *pkg = kzalloc(sizeof(*pkg), GFP_KERNEL); + if (!pkg) + return NULL; + pkg->ctl = ctl; + pkg->buffer = dma_pool_alloc(ctl->frame_pool, GFP_KERNEL, + &pkg->frame.buffer_phy); + if (!pkg->buffer) { + kfree(pkg); + return NULL; + } + return pkg; +} + + +/* RX/TX handling */ + +static void tb_ctl_tx_callback(struct tb_ring *ring, struct ring_frame *frame, + bool canceled) +{ + struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame); + tb_ctl_pkg_free(pkg); +} + +/* + * tb_cfg_tx() - transmit a packet on the control channel + * + * len must be a multiple of four. + * + * Return: Returns 0 on success or an error code on failure. + */ +static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len, + enum tb_cfg_pkg_type type) +{ + int res; + struct ctl_pkg *pkg; + if (len % 4 != 0) { /* required for le->be conversion */ + tb_ctl_WARN(ctl, "TX: invalid size: %zu\n", len); + return -EINVAL; + } + if (len > TB_FRAME_SIZE - 4) { /* checksum is 4 bytes */ + tb_ctl_WARN(ctl, "TX: packet too large: %zu/%d\n", + len, TB_FRAME_SIZE - 4); + return -EINVAL; + } + pkg = tb_ctl_pkg_alloc(ctl); + if (!pkg) + return -ENOMEM; + pkg->frame.callback = tb_ctl_tx_callback; + pkg->frame.size = len + 4; + pkg->frame.sof = type; + pkg->frame.eof = type; + cpu_to_be32_array(pkg->buffer, data, len / 4); + *(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len); + + res = tb_ring_tx(ctl->tx, &pkg->frame); + if (res) /* ring is stopped */ + tb_ctl_pkg_free(pkg); + return res; +} + +/* + * tb_ctl_handle_event() - acknowledge a plug event, invoke ctl->callback + */ +static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type, + struct ctl_pkg *pkg, size_t size) +{ + return ctl->callback(ctl->callback_data, type, pkg->buffer, size); +} + +static void tb_ctl_rx_submit(struct ctl_pkg *pkg) +{ + tb_ring_rx(pkg->ctl->rx, &pkg->frame); /* + * We ignore failures during stop. + * All rx packets are referenced + * from ctl->rx_packets, so we do + * not loose them. + */ +} + +static int tb_async_error(const struct ctl_pkg *pkg) +{ + const struct cfg_error_pkg *error = pkg->buffer; + + if (pkg->frame.eof != TB_CFG_PKG_ERROR) + return false; + + switch (error->error) { + case TB_CFG_ERROR_LINK_ERROR: + case TB_CFG_ERROR_HEC_ERROR_DETECTED: + case TB_CFG_ERROR_FLOW_CONTROL_ERROR: + case TB_CFG_ERROR_DP_BW: + case TB_CFG_ERROR_ROP_CMPLT: + case TB_CFG_ERROR_POP_CMPLT: + case TB_CFG_ERROR_PCIE_WAKE: + case TB_CFG_ERROR_DP_CON_CHANGE: + case TB_CFG_ERROR_DPTX_DISCOVERY: + case TB_CFG_ERROR_LINK_RECOVERY: + case TB_CFG_ERROR_ASYM_LINK: + return true; + + default: + return false; + } +} + +static void tb_ctl_rx_callback(struct tb_ring *ring, struct ring_frame *frame, + bool canceled) +{ + struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame); + struct tb_cfg_request *req; + __be32 crc32; + + if (canceled) + return; /* + * ring is stopped, packet is referenced from + * ctl->rx_packets. + */ + + if (frame->size < 4 || frame->size % 4 != 0) { + tb_ctl_err(pkg->ctl, "RX: invalid size %#x, dropping packet\n", + frame->size); + goto rx; + } + + frame->size -= 4; /* remove checksum */ + crc32 = tb_crc(pkg->buffer, frame->size); + be32_to_cpu_array(pkg->buffer, pkg->buffer, frame->size / 4); + + switch (frame->eof) { + case TB_CFG_PKG_READ: + case TB_CFG_PKG_WRITE: + case TB_CFG_PKG_ERROR: + case TB_CFG_PKG_OVERRIDE: + case TB_CFG_PKG_RESET: + if (*(__be32 *)(pkg->buffer + frame->size) != crc32) { + tb_ctl_err(pkg->ctl, + "RX: checksum mismatch, dropping packet\n"); + goto rx; + } + if (tb_async_error(pkg)) { + tb_ctl_handle_event(pkg->ctl, frame->eof, + pkg, frame->size); + goto rx; + } + break; + + case TB_CFG_PKG_EVENT: + case TB_CFG_PKG_XDOMAIN_RESP: + case TB_CFG_PKG_XDOMAIN_REQ: + if (*(__be32 *)(pkg->buffer + frame->size) != crc32) { + tb_ctl_err(pkg->ctl, + "RX: checksum mismatch, dropping packet\n"); + goto rx; + } + fallthrough; + case TB_CFG_PKG_ICM_EVENT: + if (tb_ctl_handle_event(pkg->ctl, frame->eof, pkg, frame->size)) + goto rx; + break; + + default: + break; + } + + /* + * The received packet will be processed only if there is an + * active request and that the packet is what is expected. This + * prevents packets such as replies coming after timeout has + * triggered from messing with the active requests. + */ + req = tb_cfg_request_find(pkg->ctl, pkg); + if (req) { + if (req->copy(req, pkg)) + schedule_work(&req->work); + tb_cfg_request_put(req); + } + +rx: + tb_ctl_rx_submit(pkg); +} + +static void tb_cfg_request_work(struct work_struct *work) +{ + struct tb_cfg_request *req = container_of(work, typeof(*req), work); + + if (!test_bit(TB_CFG_REQUEST_CANCELED, &req->flags)) + req->callback(req->callback_data); + + tb_cfg_request_dequeue(req); + tb_cfg_request_put(req); +} + +/** + * tb_cfg_request() - Start control request not waiting for it to complete + * @ctl: Control channel to use + * @req: Request to start + * @callback: Callback called when the request is completed + * @callback_data: Data to be passed to @callback + * + * This queues @req on the given control channel without waiting for it + * to complete. When the request completes @callback is called. + */ +int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req, + void (*callback)(void *), void *callback_data) +{ + int ret; + + req->flags = 0; + req->callback = callback; + req->callback_data = callback_data; + INIT_WORK(&req->work, tb_cfg_request_work); + INIT_LIST_HEAD(&req->list); + + tb_cfg_request_get(req); + ret = tb_cfg_request_enqueue(ctl, req); + if (ret) + goto err_put; + + ret = tb_ctl_tx(ctl, req->request, req->request_size, + req->request_type); + if (ret) + goto err_dequeue; + + if (!req->response) + schedule_work(&req->work); + + return 0; + +err_dequeue: + tb_cfg_request_dequeue(req); +err_put: + tb_cfg_request_put(req); + + return ret; +} + +/** + * tb_cfg_request_cancel() - Cancel a control request + * @req: Request to cancel + * @err: Error to assign to the request + * + * This function can be used to cancel ongoing request. It will wait + * until the request is not active anymore. + */ +void tb_cfg_request_cancel(struct tb_cfg_request *req, int err) +{ + set_bit(TB_CFG_REQUEST_CANCELED, &req->flags); + schedule_work(&req->work); + wait_event(tb_cfg_request_cancel_queue, !tb_cfg_request_is_active(req)); + req->result.err = err; +} + +static void tb_cfg_request_complete(void *data) +{ + complete(data); +} + +/** + * tb_cfg_request_sync() - Start control request and wait until it completes + * @ctl: Control channel to use + * @req: Request to start + * @timeout_msec: Timeout how long to wait @req to complete + * + * Starts a control request and waits until it completes. If timeout + * triggers the request is canceled before function returns. Note the + * caller needs to make sure only one message for given switch is active + * at a time. + */ +struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl, + struct tb_cfg_request *req, + int timeout_msec) +{ + unsigned long timeout = msecs_to_jiffies(timeout_msec); + struct tb_cfg_result res = { 0 }; + DECLARE_COMPLETION_ONSTACK(done); + int ret; + + ret = tb_cfg_request(ctl, req, tb_cfg_request_complete, &done); + if (ret) { + res.err = ret; + return res; + } + + if (!wait_for_completion_timeout(&done, timeout)) + tb_cfg_request_cancel(req, -ETIMEDOUT); + + flush_work(&req->work); + + return req->result; +} + +/* public interface, alloc/start/stop/free */ + +/** + * tb_ctl_alloc() - allocate a control channel + * @nhi: Pointer to NHI + * @timeout_msec: Default timeout used with non-raw control messages + * @cb: Callback called for plug events + * @cb_data: Data passed to @cb + * + * cb will be invoked once for every hot plug event. + * + * Return: Returns a pointer on success or NULL on failure. + */ +struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, int timeout_msec, event_cb cb, + void *cb_data) +{ + int i; + struct tb_ctl *ctl = kzalloc(sizeof(*ctl), GFP_KERNEL); + if (!ctl) + return NULL; + ctl->nhi = nhi; + ctl->timeout_msec = timeout_msec; + ctl->callback = cb; + ctl->callback_data = cb_data; + + mutex_init(&ctl->request_queue_lock); + INIT_LIST_HEAD(&ctl->request_queue); + ctl->frame_pool = dma_pool_create("thunderbolt_ctl", &nhi->pdev->dev, + TB_FRAME_SIZE, 4, 0); + if (!ctl->frame_pool) + goto err; + + ctl->tx = tb_ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND); + if (!ctl->tx) + goto err; + + ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0, 0xffff, + 0xffff, NULL, NULL); + if (!ctl->rx) + goto err; + + for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) { + ctl->rx_packets[i] = tb_ctl_pkg_alloc(ctl); + if (!ctl->rx_packets[i]) + goto err; + ctl->rx_packets[i]->frame.callback = tb_ctl_rx_callback; + } + + tb_ctl_dbg(ctl, "control channel created\n"); + return ctl; +err: + tb_ctl_free(ctl); + return NULL; +} + +/** + * tb_ctl_free() - free a control channel + * @ctl: Control channel to free + * + * Must be called after tb_ctl_stop. + * + * Must NOT be called from ctl->callback. + */ +void tb_ctl_free(struct tb_ctl *ctl) +{ + int i; + + if (!ctl) + return; + + if (ctl->rx) + tb_ring_free(ctl->rx); + if (ctl->tx) + tb_ring_free(ctl->tx); + + /* free RX packets */ + for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) + tb_ctl_pkg_free(ctl->rx_packets[i]); + + + dma_pool_destroy(ctl->frame_pool); + kfree(ctl); +} + +/** + * tb_ctl_start() - start/resume the control channel + * @ctl: Control channel to start + */ +void tb_ctl_start(struct tb_ctl *ctl) +{ + int i; + tb_ctl_dbg(ctl, "control channel starting...\n"); + tb_ring_start(ctl->tx); /* is used to ack hotplug packets, start first */ + tb_ring_start(ctl->rx); + for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) + tb_ctl_rx_submit(ctl->rx_packets[i]); + + ctl->running = true; +} + +/** + * tb_ctl_stop() - pause the control channel + * @ctl: Control channel to stop + * + * All invocations of ctl->callback will have finished after this method + * returns. + * + * Must NOT be called from ctl->callback. + */ +void tb_ctl_stop(struct tb_ctl *ctl) +{ + mutex_lock(&ctl->request_queue_lock); + ctl->running = false; + mutex_unlock(&ctl->request_queue_lock); + + tb_ring_stop(ctl->rx); + tb_ring_stop(ctl->tx); + + if (!list_empty(&ctl->request_queue)) + tb_ctl_WARN(ctl, "dangling request in request_queue\n"); + INIT_LIST_HEAD(&ctl->request_queue); + tb_ctl_dbg(ctl, "control channel stopped\n"); +} + +/* public interface, commands */ + +/** + * tb_cfg_ack_notification() - Ack notification + * @ctl: Control channel to use + * @route: Router that originated the event + * @error: Pointer to the notification package + * + * Call this as response for non-plug notification to ack it. Returns + * %0 on success or an error code on failure. + */ +int tb_cfg_ack_notification(struct tb_ctl *ctl, u64 route, + const struct cfg_error_pkg *error) +{ + struct cfg_ack_pkg pkg = { + .header = tb_cfg_make_header(route), + }; + const char *name; + + switch (error->error) { + case TB_CFG_ERROR_LINK_ERROR: + name = "link error"; + break; + case TB_CFG_ERROR_HEC_ERROR_DETECTED: + name = "HEC error"; + break; + case TB_CFG_ERROR_FLOW_CONTROL_ERROR: + name = "flow control error"; + break; + case TB_CFG_ERROR_DP_BW: + name = "DP_BW"; + break; + case TB_CFG_ERROR_ROP_CMPLT: + name = "router operation completion"; + break; + case TB_CFG_ERROR_POP_CMPLT: + name = "port operation completion"; + break; + case TB_CFG_ERROR_PCIE_WAKE: + name = "PCIe wake"; + break; + case TB_CFG_ERROR_DP_CON_CHANGE: + name = "DP connector change"; + break; + case TB_CFG_ERROR_DPTX_DISCOVERY: + name = "DPTX discovery"; + break; + case TB_CFG_ERROR_LINK_RECOVERY: + name = "link recovery"; + break; + case TB_CFG_ERROR_ASYM_LINK: + name = "asymmetric link"; + break; + default: + name = "unknown"; + break; + } + + tb_ctl_dbg(ctl, "acking %s (%#x) notification on %llx\n", name, + error->error, route); + + return tb_ctl_tx(ctl, &pkg, sizeof(pkg), TB_CFG_PKG_NOTIFY_ACK); +} + +/** + * tb_cfg_ack_plug() - Ack hot plug/unplug event + * @ctl: Control channel to use + * @route: Router that originated the event + * @port: Port where the hot plug/unplug happened + * @unplug: Ack hot plug or unplug + * + * Call this as response for hot plug/unplug event to ack it. + * Returns %0 on success or an error code on failure. + */ +int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug) +{ + struct cfg_error_pkg pkg = { + .header = tb_cfg_make_header(route), + .port = port, + .error = TB_CFG_ERROR_ACK_PLUG_EVENT, + .pg = unplug ? TB_CFG_ERROR_PG_HOT_UNPLUG + : TB_CFG_ERROR_PG_HOT_PLUG, + }; + tb_ctl_dbg(ctl, "acking hot %splug event on %llx:%u\n", + unplug ? "un" : "", route, port); + return tb_ctl_tx(ctl, &pkg, sizeof(pkg), TB_CFG_PKG_ERROR); +} + +static bool tb_cfg_match(const struct tb_cfg_request *req, + const struct ctl_pkg *pkg) +{ + u64 route = tb_cfg_get_route(pkg->buffer) & ~BIT_ULL(63); + + if (pkg->frame.eof == TB_CFG_PKG_ERROR) + return true; + + if (pkg->frame.eof != req->response_type) + return false; + if (route != tb_cfg_get_route(req->request)) + return false; + if (pkg->frame.size != req->response_size) + return false; + + if (pkg->frame.eof == TB_CFG_PKG_READ || + pkg->frame.eof == TB_CFG_PKG_WRITE) { + const struct cfg_read_pkg *req_hdr = req->request; + const struct cfg_read_pkg *res_hdr = pkg->buffer; + + if (req_hdr->addr.seq != res_hdr->addr.seq) + return false; + } + + return true; +} + +static bool tb_cfg_copy(struct tb_cfg_request *req, const struct ctl_pkg *pkg) +{ + struct tb_cfg_result res; + + /* Now make sure it is in expected format */ + res = parse_header(pkg, req->response_size, req->response_type, + tb_cfg_get_route(req->request)); + if (!res.err) + memcpy(req->response, pkg->buffer, req->response_size); + + req->result = res; + + /* Always complete when first response is received */ + return true; +} + +/** + * tb_cfg_reset() - send a reset packet and wait for a response + * @ctl: Control channel pointer + * @route: Router string for the router to send reset + * + * If the switch at route is incorrectly configured then we will not receive a + * reply (even though the switch will reset). The caller should check for + * -ETIMEDOUT and attempt to reconfigure the switch. + */ +struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route) +{ + struct cfg_reset_pkg request = { .header = tb_cfg_make_header(route) }; + struct tb_cfg_result res = { 0 }; + struct tb_cfg_header reply; + struct tb_cfg_request *req; + + req = tb_cfg_request_alloc(); + if (!req) { + res.err = -ENOMEM; + return res; + } + + req->match = tb_cfg_match; + req->copy = tb_cfg_copy; + req->request = &request; + req->request_size = sizeof(request); + req->request_type = TB_CFG_PKG_RESET; + req->response = &reply; + req->response_size = sizeof(reply); + req->response_type = TB_CFG_PKG_RESET; + + res = tb_cfg_request_sync(ctl, req, ctl->timeout_msec); + + tb_cfg_request_put(req); + + return res; +} + +/** + * tb_cfg_read_raw() - read from config space into buffer + * @ctl: Pointer to the control channel + * @buffer: Buffer where the data is read + * @route: Route string of the router + * @port: Port number when reading from %TB_CFG_PORT, %0 otherwise + * @space: Config space selector + * @offset: Dword word offset of the register to start reading + * @length: Number of dwords to read + * @timeout_msec: Timeout in ms how long to wait for the response + * + * Reads from router config space without translating the possible error. + */ +struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer, + u64 route, u32 port, enum tb_cfg_space space, + u32 offset, u32 length, int timeout_msec) +{ + struct tb_cfg_result res = { 0 }; + struct cfg_read_pkg request = { + .header = tb_cfg_make_header(route), + .addr = { + .port = port, + .space = space, + .offset = offset, + .length = length, + }, + }; + struct cfg_write_pkg reply; + int retries = 0; + + while (retries < TB_CTL_RETRIES) { + struct tb_cfg_request *req; + + req = tb_cfg_request_alloc(); + if (!req) { + res.err = -ENOMEM; + return res; + } + + request.addr.seq = retries++; + + req->match = tb_cfg_match; + req->copy = tb_cfg_copy; + req->request = &request; + req->request_size = sizeof(request); + req->request_type = TB_CFG_PKG_READ; + req->response = &reply; + req->response_size = 12 + 4 * length; + req->response_type = TB_CFG_PKG_READ; + + res = tb_cfg_request_sync(ctl, req, timeout_msec); + + tb_cfg_request_put(req); + + if (res.err != -ETIMEDOUT) + break; + + /* Wait a bit (arbitrary time) until we send a retry */ + usleep_range(10, 100); + } + + if (res.err) + return res; + + res.response_port = reply.addr.port; + res.err = check_config_address(reply.addr, space, offset, length); + if (!res.err) + memcpy(buffer, &reply.data, 4 * length); + return res; +} + +/** + * tb_cfg_write_raw() - write from buffer into config space + * @ctl: Pointer to the control channel + * @buffer: Data to write + * @route: Route string of the router + * @port: Port number when writing to %TB_CFG_PORT, %0 otherwise + * @space: Config space selector + * @offset: Dword word offset of the register to start writing + * @length: Number of dwords to write + * @timeout_msec: Timeout in ms how long to wait for the response + * + * Writes to router config space without translating the possible error. + */ +struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, const void *buffer, + u64 route, u32 port, enum tb_cfg_space space, + u32 offset, u32 length, int timeout_msec) +{ + struct tb_cfg_result res = { 0 }; + struct cfg_write_pkg request = { + .header = tb_cfg_make_header(route), + .addr = { + .port = port, + .space = space, + .offset = offset, + .length = length, + }, + }; + struct cfg_read_pkg reply; + int retries = 0; + + memcpy(&request.data, buffer, length * 4); + + while (retries < TB_CTL_RETRIES) { + struct tb_cfg_request *req; + + req = tb_cfg_request_alloc(); + if (!req) { + res.err = -ENOMEM; + return res; + } + + request.addr.seq = retries++; + + req->match = tb_cfg_match; + req->copy = tb_cfg_copy; + req->request = &request; + req->request_size = 12 + 4 * length; + req->request_type = TB_CFG_PKG_WRITE; + req->response = &reply; + req->response_size = sizeof(reply); + req->response_type = TB_CFG_PKG_WRITE; + + res = tb_cfg_request_sync(ctl, req, timeout_msec); + + tb_cfg_request_put(req); + + if (res.err != -ETIMEDOUT) + break; + + /* Wait a bit (arbitrary time) until we send a retry */ + usleep_range(10, 100); + } + + if (res.err) + return res; + + res.response_port = reply.addr.port; + res.err = check_config_address(reply.addr, space, offset, length); + return res; +} + +static int tb_cfg_get_error(struct tb_ctl *ctl, enum tb_cfg_space space, + const struct tb_cfg_result *res) +{ + /* + * For unimplemented ports access to port config space may return + * TB_CFG_ERROR_INVALID_CONFIG_SPACE (alternatively their type is + * set to TB_TYPE_INACTIVE). In the former case return -ENODEV so + * that the caller can mark the port as disabled. + */ + if (space == TB_CFG_PORT && + res->tb_error == TB_CFG_ERROR_INVALID_CONFIG_SPACE) + return -ENODEV; + + tb_cfg_print_error(ctl, res); + + if (res->tb_error == TB_CFG_ERROR_LOCK) + return -EACCES; + if (res->tb_error == TB_CFG_ERROR_PORT_NOT_CONNECTED) + return -ENOTCONN; + + return -EIO; +} + +int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port, + enum tb_cfg_space space, u32 offset, u32 length) +{ + struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer, route, port, + space, offset, length, ctl->timeout_msec); + switch (res.err) { + case 0: + /* Success */ + break; + + case 1: + /* Thunderbolt error, tb_error holds the actual number */ + return tb_cfg_get_error(ctl, space, &res); + + case -ETIMEDOUT: + tb_ctl_warn(ctl, "%llx: timeout reading config space %u from %#x\n", + route, space, offset); + break; + + default: + WARN(1, "tb_cfg_read: %d\n", res.err); + break; + } + return res.err; +} + +int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port, + enum tb_cfg_space space, u32 offset, u32 length) +{ + struct tb_cfg_result res = tb_cfg_write_raw(ctl, buffer, route, port, + space, offset, length, ctl->timeout_msec); + switch (res.err) { + case 0: + /* Success */ + break; + + case 1: + /* Thunderbolt error, tb_error holds the actual number */ + return tb_cfg_get_error(ctl, space, &res); + + case -ETIMEDOUT: + tb_ctl_warn(ctl, "%llx: timeout writing config space %u to %#x\n", + route, space, offset); + break; + + default: + WARN(1, "tb_cfg_write: %d\n", res.err); + break; + } + return res.err; +} + +/** + * tb_cfg_get_upstream_port() - get upstream port number of switch at route + * @ctl: Pointer to the control channel + * @route: Route string of the router + * + * Reads the first dword from the switches TB_CFG_SWITCH config area and + * returns the port number from which the reply originated. + * + * Return: Returns the upstream port number on success or an error code on + * failure. + */ +int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route) +{ + u32 dummy; + struct tb_cfg_result res = tb_cfg_read_raw(ctl, &dummy, route, 0, + TB_CFG_SWITCH, 0, 1, + ctl->timeout_msec); + if (res.err == 1) + return -EIO; + if (res.err) + return res.err; + return res.response_port; +} |